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1.
论述了GSM-R无线网络与高速列车关系,为保证列控信息可靠传输对GSM-R网络覆盖提出了要求,对深度冗余的GSM-R网络运行进行了具体的分析。对GSM-R无线网络设备给出了具体的性能指标。 相似文献
2.
针对一种全新在流化床锅炉生产过程中进行监视、操作、管理和分散控制的分布式计算机控制系统—集散控制系统（DCS）的应用情况,主要分析了DCS在锅炉系统中的特点、配置、网络结构和功能运用。锅炉DCS系统投运后,运行良好,各项功能达到设计要求。 相似文献
3.
本文介绍了火力发电厂电气控制系统的两种控制模式,即电气现场总线控制系统（EFCS系统）和电气控制管理系统（ECMS系统）,并对这两种控制模式的主要设计模式和监控对象进行了分析比较。ECMS系统不与DCS系统通信,没有减少电气设备进入DCS系统的I/O硬接线。在EFCS系统方案中,小型电动机采用＂全通信＂监控方式进DCS系统,大型电动机及其他电气设备采用＂通信＋硬接线＂监控方式。E-FCS系统与DCS系统进行了网络互联,实现了信息共享,避免了信息重复采集,从而减少了设备和电缆成本及运行维护费用。 相似文献
4.
提出了一种用于LTE网络中头标压缩功能的上下文转移方案,可以用来减小无线链路上的报文开销,降低切换时的信令时延,从而提高整个通信网络的效率. 文中对头标压缩的上下文转移过程进行了详细描述,包括信令报文的处理、上下文转移参数的重建以及头标压缩状态的变迁. 通过仿真分析,对方案的有效性进行了验证.该方案适用于语音通信为主的无线通信网络. 相似文献
5.
本文介绍了利用铁路专用移动通信网承载铁路机车信号远程动态监测系统的组网结构、通信原理、技术特点。并对承载机车信号远程动态监测系统的GPRS网络进行了网络功能分析,提出了具体网络设置、维护方面的建议。 相似文献
6.
In this paper, the distributed fault diagnosis (DFD) of networked dynamical systems with time-varying connected topologies, e.g., wireless sensor networks in harsh environments, is considered. Specifically, two essential problems are focused on, which are faced in extending the the decomposition-based adaptive DFD approach to such topology-varying systems. The problems introduced by the time-varying topologies are, respectively, decomposition schemes deterioration and pre-training difficulties. The causes of the two problems are detailed and addressed in our work. First, for the decomposition schemes deterioration problem, a multi-agent dynamics-based online distributed decomposition algorithm are developed, so that a decent decomposed network structure for such topology-varying network can be maintained. Second, to alleviate the pre-training difficulties in topology-varying systems, a fault detection method is proposed, which avoids the need for pre-training. The distributed decomposition algorithm is proved to converge in finite steps, and the proposed fault detection method is verified both theoretically and experimentally. 相似文献
7.
With the deployment of fifth-generation (5G) wireless networks worldwide, research on sixth-generation (6G) wireless communications has commenced. It is expected that 6G networks can accommodate numerous heterogeneous devices and infrastructures with enhanced efficiency and security over diverse, e.g. spectrum, computing and storage, resources. However, this goal is impeded by a number of trust-related issues that are often neglected in network designs. Blockchain, as an innovative and revolutionary technology that has arisen in the recent decade, provides a promising solution. Building on its nature of decentralization, transparency, anonymity, immutability, traceability and resiliency, blockchain can establish cooperative trust among separate network entities and facilitate, e.g. efficient resource sharing, trusted data interaction, secure access control, privacy protection, and tracing, certification and supervision functionalities for wireless networks, thus presenting a new paradigm towards 6G. This paper is dedicated to blockchain-enabled wireless communication technologies. We first provide a brief introduction to the fundamentals of blockchain, and then we conduct a comprehensive investigation of the most recent efforts in incorporating blockchain into wireless communications from several aspects. Importantly, we further propose a unified framework of the blockchain radio access network (B-RAN) as a trustworthy and secure paradigm for 6G networking by utilizing blockchain technologies with enhanced efficiency and security. The critical elements of B-RAN, such as consensus mechanisms, smart contract, trustworthy access, mathematical modeling, cross-network sharing, data tracking and auditing and intelligent networking, are elaborated. We also provide the prototype design of B-RAN along with the latest experimental results. 相似文献
8.
《Journal of The Franklin Institute》2022,359(8):3389-3404
Power systems are subject to stochastic faults and process random noise. The faults (due to e.g. lightning strokes) can be temporary or permanent. When a lightning stroke hits a transmission line, the circuit breakers open to clear the fault and reclose. The resulting parameters changes are modelled as a discrete-time Markov jumps in this paper using the practical statistical failure rates. System parameters are also subject to random noise e.g. line reactance’s depend on the conductors spacing which in turn depends on stochastic wind speeds. This paper presents a novel power system excitation control robust against such stochastic uncertainties. The design is based on a derived sufficient condition in the framework of linear matrix inequalities (LMI), and the attracting ellipsoid approach. The effectiveness of the proposed control is tested on a multi-machine power system. 相似文献
9.
本文主要从DCS系统角度出发,在DCS系统厂商已确定的前提下,对DCS系统的控制设计、安装运行、基础管理和工作人员职业素质进行了探讨分析,找到了影响DCS系统稳定性的原因,提出了提高DCS系统稳定性的一些原则和要求,以及在DCS系统应用中需要解决和注意的问题。 相似文献
10.
为了提高第3代移动通信技术在无线接入领域的竞争力,3GPP提出了第3代移动通信的长期演进计划,即LTE。本文介绍了引入3GPPLTE目地以及它的目标和需求,重点研究了上行链路中的几个关键技术,最后对LTE的发展趋势进行了讨论。 相似文献
11.
本文提出了一种以ARM和嵌入式技术为基础,采用CDMA无线网络实现火车车头定位及图像显示的实时监控系统。文章阐明了该系统终端的总体结构和各个组成模块,分析了图像显示、无线定位和自动报警的具体功能和软件实现。经过试验测试表明,该系统能够实时定位并显示车体运行状况的数据。 相似文献
12.
With the development of information technology and economic growth, the Internet of Things (IoT) industry has also entered the fast lane of development. The IoT industry system has also gradually improved, forming a complete industrial foundation, including chips, electronic components, equipment, software, integrated systems, IoT services, and telecom operators. In the event of selective forwarding attacks, virus damage, malicious virus intrusion, etc., the losses caused by such security problems are more serious than those of traditional networks, which are not only network information materials, but also physical objects. The limitations of sensor node resources in the Internet of Things, the complexity of networking, and the open wireless broadcast communication characteristics make it vulnerable to attacks. Intrusion Detection System (IDS) helps identify anomalies in the network and takes the necessary countermeasures to ensure the safe and reliable operation of IoT applications. This paper proposes an IoT feature extraction and intrusion detection algorithm for intelligent city based on deep migration learning model, which combines deep learning model with intrusion detection technology. According to the existing literature and algorithms, this paper introduces the modeling scheme of migration learning model and data feature extraction. In the experimental part, KDD CUP 99 was selected as the experimental data set, and 10% of the data was used as training data. At the same time, the proposed algorithm is compared with the existing algorithms. The experimental results show that the proposed algorithm has shorter detection time and higher detection efficiency. 相似文献
13.
In this study, an adaptive fractional order sliding mode controller with a neural estimator is proposed for a class of systems with nonlinear disturbances. Compared with traditional sliding mode controller, the new proposed fractional order sliding mode controller contains a fractional order term in the sliding surface. The fractional order sliding surface is used in adaptive laws which are derived in the framework of Lyapunov stability theory. The bound of the disturbances is estimated by a radial basis function neural network to relax the requirement of disturbance bound. To investigate the effectiveness of the proposed adaptive neural fractional order sliding mode controller, the methodology is applied to a Z-axis Micro-Electro-Mechanical System (MEMS) gyroscope to control the vibrating dynamics of the proof mass. Simulation results demonstrate that the proposed control system can improve tracking performance as well as parameter identification performance. 相似文献
14.
介绍了一种基于GPRS无线网络的在线烟气监测系统（Continuous Emission Monitoring System,CEMS）,通过在线测试技术,能够实时监测工厂烟气排放情况。利用GPRS无线通信技术可以实现工作现场、控制终端和环境保护部门的数据共享。同时,也可以通过Web页面发布方式将数据实时发布给公众。该烟气在线监测系统具有传输方式无线化、数据发布多样化的特点,具有广阔的应用前景。 相似文献
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16.
《Journal of The Franklin Institute》2022,359(17):9703-9733
This paper addresses the problem of efficient control of nonlinear distributed networked control systems in the presence of stochastic deception attacks and time-varying coupling strength. A strategy combining model-based and event-triggered control to reduce the number of transmissions over a network thereby, saving network resources is proposed. In this strategy, a plant model at the controller end is used to estimate the state of each subsystem. Further, the control law between the two adjacent triggering instants changes in accordance with dynamics of the plant model. The nonlinearities present in each subsystem are approximated via neural network. The neural network weights and feedback signal are updated only when the event-triggering condition at the sensor end is violated. Also, a lower bound on the inter-event time is computed to avoid the occurrence of Zeno phenomena. Finally, the efficacy of the proposed methodology are verified through simulation examples. 相似文献
17.
提出了一种基于GPRS的无线煤矿监测监控系统方案,矿井监控计算机将采集到的数据及报警信息利用移动网的GPRS无线网络可以及时发送到政府监控中心。该系统实现了分散煤矿信息采集的自动化,具有及时、高效、准确、基建投资少、运行成本低等特点,具有显著的社会效益和较大的经济效益。 相似文献
18.
丁勇 《科技成果管理与研究》2011,(6):80-82,88
文章简述了机电一体化配料秤相对于传统配料秤的特点以及它通过PROFIBUS DP网络与过程控制系统（DCS）之间的网络连接情况,同时也简述了在DCS控制系统里组态与控制的过程以及机电一体化配料秤在烧结厂的使用情况和由此而带来的经济效益。 相似文献
19.
Lianghong Peng Xianghui Cao Hongbao Shi Changyin Sun 《Journal of The Franklin Institute》2018,355(14):6859-6876
In cyber-physical systems (CPS), cyber threats emerge in many ways which can cause significant destruction to the system operation. In wireless CPS, adversaries can block the communications of useful information by channel jamming, incurring the so-called denial of service (DoS) attacks. In this paper, we investigate the problem of optimal jamming attack scheduling against remote state estimation wireless network. Specifically, we consider that two wireless sensors report data to a remote estimator through two wireless communication channels lying in two unoverlapping frequency bands, respectively. Meanwhile, an adversary can select one and only one channel at a time to execute jamming attack. We prove that the optimal attack schedule is continuously launching attack on one channel determined based on the system dynamics matrix. The theoretical results are validated by numerical simulations. 相似文献
20.
在LTE网络中,用户附着机制是LTE业务实现的一项关键技术,但是复杂的网络环境影响LTE用户的正常附着。根据实际运营中遇到的用户附着问题,在深入分析问题原因的基础上,提出了相应的解决方案,并取得了良好的效果。 相似文献